涡轮表面腐蚀原因分析

Failure Analysis of Turbine Surface's Corrosion

镍基高温合金涡轮在运行一段时间后表面发生了严重腐蚀、叶片尺寸减小。通过对涡轮表面观察、测试与分析,确定了涡轮表面腐蚀为热腐蚀,腐蚀机理为钠盐热腐蚀,腐蚀介质为含硫钠盐,随着热腐蚀的加重,腐蚀产物不断剥落,导致叶片尺寸逐渐减小。涡轮表面发生热腐蚀原因是由于发动机燃油燃烧不充分,导致表面接触甚至沉积含硫钠盐,在发动机高温的共同作用下发生热腐蚀。

Nickel-alloy turbine was corroded after worked for a period of time. The size of turbine blades became smaller. Through observation, testing, the corrosion reason of the tubine was found. The results show that the corrosion was sodium salt hot-corrosion. The oxide was fell off which made the size of turbine blade became samaller. Because the fuel oil was not burned all, some sodium-salt deposited on the turbine＇s surface, which made the tubine corroded.